monin_obukhov.F90

!***********************************************************************
!*                   GNU Lesser General Public License
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!* This file is part of the GFDL Flexible Modeling System (FMS).
!*
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!***********************************************************************
!> @defgroup monin_obukhov_mod monin_obukhov_mod
!> @ingroup monin_obukhov
!> @brief Routines for computing surface drag coefficients
!! from data at the lowest model level
!! and for computing the profile of fields
!! between the lowest model level and the ground
!! using Monin-Obukhov scaling
 
module monin_obukhov_mod
 
use constants_mod, only: grav, vonkarm
use mpp_mod,       only: input_nml_file
use fms_mod,       only: error_mesg, fatal, check_nml_error,   &
                         mpp_pe, mpp_root_pe, stdlog, &
                         write_version_number
use monin_obukhov_inter, only: monin_obukhov_diff, monin_obukhov_drag_1d, &
                               monin_obukhov_profile_1d, monin_obukhov_stable_mix
use platform_mod,        only: r4_kind, r8_kind
implicit none
private
 
!=======================================================================
 public :: monin_obukhov_init
 public :: monin_obukhov_end
 public :: mo_drag
 public :: mo_profile
 public :: mo_diff
 public :: stable_mix
!=======================================================================
 
!> @brief Compute surface drag coefficients
!> @ingroup monin_obukhov_mod
interface mo_drag
    module procedure mo_drag_0d_r4, mo_drag_0d_r8
    module procedure mo_drag_1d_r4, mo_drag_1d_r8
    module procedure mo_drag_2d_r4, mo_drag_2d_r8
end interface
 
 
!> @ingroup monin_obukhov_mod
interface mo_profile
    module procedure mo_profile_0d_r4, mo_profile_0d_r8
    module procedure mo_profile_1d_r4, mo_profile_1d_r8
    module procedure mo_profile_2d_r4, mo_profile_2d_r8
    module procedure mo_profile_0d_n_r4, mo_profile_0d_n_r8
    module procedure mo_profile_1d_n_r4, mo_profile_1d_n_r8
    module procedure mo_profile_2d_n_r4, mo_profile_2d_n_r8
end interface
 
!> @ingroup monin_obukhov_mod
interface mo_diff
    module procedure mo_diff_0d_n_r4, mo_diff_0d_n_r8
    module procedure mo_diff_0d_1_r4, mo_diff_0d_1_r8
    module procedure mo_diff_1d_n_r4, mo_diff_1d_n_r8
    module procedure mo_diff_1d_1_r4, mo_diff_1d_1_r8
    module procedure mo_diff_2d_n_r4, mo_diff_2d_n_r8
    module procedure mo_diff_2d_1_r4, mo_diff_2d_1_r8
end interface
 
!> @ingroup monin_obukhov_mod
interface stable_mix
    module procedure stable_mix_0d_r4, stable_mix_0d_r8
    module procedure stable_mix_1d_r4, stable_mix_1d_r8
    module procedure stable_mix_2d_r4, stable_mix_2d_r8
    module procedure stable_mix_3d_r4, stable_mix_3d_r8
end interface
 
interface mo_integral_m
    module procedure mo_integral_m_r4, mo_integral_m_r8
end interface mo_integral_m
 
interface mo_integral_tq
    module procedure mo_integral_tq_r4, mo_integral_tq_r8
end interface mo_integral_tq
 
interface mo_derivative_m
    module procedure mo_derivative_m_r4, mo_derivative_m_r8
end interface mo_derivative_m
 
interface mo_derivative_t
    module procedure mo_derivative_t_r4, mo_derivative_t_r8
end interface mo_derivative_t
!> @addtogroup monin_obukhov_mod
!> @{
 
!-----------------------------------------------------------------------
! version number of this module
! Include variable "version" to be written to log file.
#include<file_version.h>
 
!=======================================================================
 
!  DEFAULT VALUES OF NAMELIST PARAMETERS:
 
real(kind=r8_kind) :: rich_crit      = 2.0_r8_kind
real(kind=r8_kind) :: drag_min_heat  = 1.0e-05_r8_kind
real(kind=r8_kind) :: drag_min_moist = 1.0e-05_r8_kind
real(kind=r8_kind) :: drag_min_mom   = 1.0e-05_r8_kind
logical            :: neutral        = .false.
integer            :: stable_option  = 1
real(kind=r8_kind) :: zeta_trans     = 0.5_r8_kind
logical            :: new_mo_option  = .false.
 
 
namelist /monin_obukhov_nml/ rich_crit, neutral, drag_min_heat, &
                             drag_min_moist, drag_min_mom,      &
                             stable_option, zeta_trans, new_mo_option !miz
 
!=======================================================================
 
!  MODULE VARIABLES
 
real(kind=r8_kind), parameter    :: small  = 1.0e-04_r8_kind
real(kind=r8_kind)               :: b_stab, r_crit, lambda, rich_trans
real(kind=r8_kind)               :: sqrt_drag_min_heat, sqrt_drag_min_moist, sqrt_drag_min_mom
logical                          :: module_is_initialized = .false.
 
 
contains
 
!=======================================================================
 
subroutine monin_obukhov_init
 
integer :: ierr, io, logunit
 
!------------------- read namelist input -------------------------------
 
      read (input_nml_file, nml=monin_obukhov_nml, iostat=io)
      ierr = check_nml_error(io,"monin_obukhov_nml")
 
!---------- output namelist to log-------------------------------------
 
      if ( mpp_pe() == mpp_root_pe() ) then
           call write_version_number('MONIN_OBUKOV_MOD', version)
           logunit = stdlog()
           write (logunit, nml=monin_obukhov_nml)
      endif
 
!----------------------------------------------------------------------
 
if(rich_crit.le.0.25_r8_kind)  call error_mesg( &
        'MONIN_OBUKHOV_INIT in MONIN_OBUKHOV_MOD', &
        'rich_crit in monin_obukhov_mod must be > 0.25', fatal)
 
if(drag_min_heat.le.0.0_r8_kind)  call error_mesg( &
        'MONIN_OBUKHOV_INIT in MONIN_OBUKHOV_MOD', &
        'drag_min_heat in monin_obukhov_mod must be >= 0.0', fatal)
 
if(drag_min_moist.le.0.0_r8_kind)  call error_mesg( &
        'MONIN_OBUKHOV_INIT in MONIN_OBUKHOV_MOD', &
        'drag_min_moist in monin_obukhov_mod must be >= 0.0', fatal)
 
if(drag_min_mom.le.0.0_r8_kind)  call error_mesg( &
        'MONIN_OBUKHOV_INIT in MONIN_OBUKHOV_MOD', &
        'drag_min_mom in monin_obukhov_mod must be >= 0.0', fatal)
 
if(stable_option < 1 .or. stable_option > 2) call error_mesg( &
        'MONIN_OBUKHOV_INIT in MONIN_OBUKHOV_MOD', &
        'the only allowable values of stable_option are 1 and 2', fatal)
 
if(stable_option == 2 .and. zeta_trans < 0) call error_mesg( &
        'MONIN_OBUKHOV_INIT in MONIN_OBUKHOV_MOD', &
        'zeta_trans must be positive', fatal)
 
b_stab = 1.0_r8_kind/rich_crit
r_crit = 0.95_r8_kind*rich_crit  ! convergence can get slow if one is
                         ! close to rich_crit
 
sqrt_drag_min_heat = 0.0_r8_kind
if(drag_min_heat.ne.0.0_r8_kind) sqrt_drag_min_heat = sqrt(drag_min_heat)
 
sqrt_drag_min_moist = 0.0_r8_kind
if(drag_min_moist.ne.0.0_r8_kind) sqrt_drag_min_moist = sqrt(drag_min_moist)
 
sqrt_drag_min_mom = 0.0_r8_kind
if(drag_min_mom.ne.0.0_r8_kind) sqrt_drag_min_mom = sqrt(drag_min_mom)
 
lambda     = 1.0_r8_kind + (5.0_r8_kind - b_stab)*zeta_trans   ! used only if stable_option = 2
rich_trans = zeta_trans/(1.0_r8_kind + 5.0_r8_kind*zeta_trans) ! used only if stable_option = 2
 
module_is_initialized = .true.
 
return
end subroutine monin_obukhov_init
 
!=======================================================================
 
subroutine monin_obukhov_end
 
module_is_initialized = .false.
 
end subroutine monin_obukhov_end
 
!=======================================================================
 
#include "monin_obukhov_r4.fh"
#include "monin_obukhov_r8.fh"
 
end module monin_obukhov_mod
!> @}
! close documentation grouping